Presentations: Before/After

Two edubloggers, Damian Bariexca and Ben Wildeboer, posted classroom presentations within minutes of each other, both having updated them for student engagement and visual prettiness.



[fixed names; thanks, h.]

The Principle Improvement

Their “before” slidedecks are dense with information. Their “before” slidedecks function as effective summaries of their lectures, which is a trait shared by absolutely every lousy slidedeck ever.

Their “after” slidedecks are image-heavy and information-light. They’re simply projecting images – no effects, no animation, no bullets – and, though we can debate the appropriateness of the images and the value they add to the lecture, no longer are Bariexca or Wildeboer trying to corral their entire talk within a 640×480 screen, which is death.

I Pity Them

But I pity these boys. I can predict their descent into madness ’cause I’m living it daily.

First, they’ll grow bored of punching keywords into FlickrCC. They’ll start searching out primary sources: satellite images, images from AP, Reuters, and Google searches.

Then they’ll start noticing extensions to their classroom content in the world around them and start snapping their own photos, creating their own Venn diagrams, building hyper-relevant discussions around those images.

Then these parasites will move to moving pictures, downloading clips from YouTube, from TV shows, building discussions around video.

Then, when they start bumping against that ceiling, they’ll make video content themselves and, from there, they’re properly screwed.

The Critical Question

But why use images at all?

What value does a submerged scuba diver add to Wildeboer’s discussion of the Earth’s crust? What value does a vampiric Hasidic Jew add to Damian’s discussion of anti-SemitismSeriously, wtf??

To some extent, their images merely season lectures which already tasted fine. Now that they’ve pushed past bullet points, it’s time for them find images which entertain and engage.

For My Part

Though I haven’t found the end of this rabbit-hole, I know I wouldn’t be half the teacher without this ability to put any image I want in front of my students.

Like today, discussing similar figures and scale-drawn maps, we hunted the Meyer family treasure across San Francisco’s financial district using some stitched-together Google Maps:

A student came in late and I caught him up by shuffling back through the slidedeck, getting him started, all with a wireless remote, all from his desk.

Afterwards I asked myself, how did this happen before?, and I couldn’t say.

I'm Dan and this is my blog. I'm a former high school math teacher and current head of teaching at Desmos. He / him. More here.


  1. OK, here’s the deal with that picture: blood libels accuse a group of people of ritual cannibalism or ingesting of blood.

    In the case of medieval Jews, one of the more popular myths that circulated was that Jews hunted and killed Christian children, using their blood to make Passover matzohs. Believe it or not, these myths persist well into the 21st century (in 2002, a Saudi newspaper claimed Jews used blood of gentile children to make homentashen), and were responsible for fueling large scale acts of violence against Jews across Europe – see here for a decent-sized list of blood libels against Jews.

    In that context, does the use of that picture make a little more sense? I know it’s bizarre, but go ahead and look up some of the European artistic depictions of Jews from the Middle Ages – this campy fellow pales in comparison to the legitimacy that governments and religious leaders bestowed upon these stories.

  2. H., thanks.

    TMAO, we’re doorbell ditching next time.

    Damian, talk about getting to have your cake and eat it too. I retract my criticism. Good slide.